|The Presidential vote can provide a nice piece of insight into the national landscape and even on a local level. The problem with putting too much faith in these numbers is that they are heavily influence by the two candidates who ran for President. A great candidate/campaign or a bad one will skew the results. And we know that neither of those guys will be running for congress any time soon.
The House vote provides a better insight, although it's not perfect. There are districts where one party isn't trying or an incumbent has huge crossover support. We have 6 districts with two Democrats 2 with two Republicans, some with no major party candidate, and 6 where the vote wasn't even counted.
Since we get that on both sides some of these issues cancel each other out. Here is the current national Presidential vote:
Now the House vote:
House Democrats had 7.5 million less votes than Obama, while House Republicans had 4.5 million less votes than Romney. Some of the Democratic congressional voters were Romney or third party voters. Obviously in a district like CA-30 where no Republican was on the ballot, most Romney voters had to choose between Howard Berman or Brad Sherman.
Democrats may win elections in years to come, but we don't know how well they'll hold the Obama coalition together. We do know that they had trouble holding some of them even as far as halfway down the page.